FA
20/9/08
Math7c
Day 13

Big Idea: Observation and description of changes in the world around us are the first steps in finding and learning about patterns.

Essential Question: How can I use graphs, tables and symbols to solve problems?

4.3 And F.U.

Notes: A Rule has to have an ‘is’ in it to be a Rule. An Equation has to have an ‘=’ in it to be an Equation. ‘Is’ = ‘=’. ‘n’ stands for the number of customers. You will need to use your table from problem 3.4.

4.3- Calculating Costs and Profits
A. Write an equation for the rule to calculate each of the following cost for each number, n, of customers.
1. Bike rental A1) b=30n 2. food and camp costs A2) f=125n
3. Van rental A3) v=700

B. Write an equation for the rule to determine the total cost for any number, ‘n’, of customers.
B) t=855n

C. Write an equation for the rule to determine the profit for any number, ‘n’, of customers.
C) p=-505n

Follow up- 4.3
1. Theo’s father has a van he will let the students use at no charge. Which of these equations represents the total cost if they use his van?
A. c=125=30 B. c=125n+30
C. c=155 D. c=155+n
1) B

2. If the partners require the customers to supply their own bikes, which of these is the new equation for total cost? (Assume the students will rent a van.)
A. c=125n+700 B. c=125+700+n
C. c=825n D. c=350n+125n+700
2) A

3. If customers must supply their own bikes, which of the equations below represent the profit? (Assume the students will rent a van.)
A. p=350-(125+700+n) B. p=350n-125n+700
C. p=350-(125n+700) D. p=350-125n-700
3) D